We begin with an arrest in the killing of the young actress found dead after a "fiddler on the roof" cast party. The suspect is one of her high school cast mates. Reporter: Good morning, george. Many in the tiny town couldn't understand how why anyone would want jessica dead or how she was killed in her own bedroom. Now, the man who allegedly did it, was a high school classmate, who confessed he has feeling for her. Police say this man brutally strangled jessie after her star turn in "fiddler on the roof." On wednesday, a wisconsin court charged him with first-degree homicide. You understand the charges? Reporter: Police called the murder gruesome and calculated. Court documents the teen's duct tape, and twine. Items that were dumped at this park, where he was allegedly captured by surveillance cameras on the day of the murder. Was analyzed for dna. Dna was preliminarily identified on that item for miss for and mr. Reporter: The news has stunned many in this tiny town who remember bartells mainly as a shy student. In high school, she and her alleged killer sang together in the choir. And in may, she posted this duet with him to youtube. Friends of the pair tell abc news, after briefly dating as freshmen, the two remained friends. But recently, bartel wanted something more. Feelings his alleged victim didn't share. Lawyers for the defense and prosecution say, for months, bartel had been unraveling, dropping out of college and pretending to go to work at a job he lost. Police say he admittedly to violently attacking another woman. In court wednesday, he sat stone-faced as his attorney argued he is not mentally fit for trial. I didn't raise the issue based upon so much my contact with daniel. As the information that I got from his parents, from a historical standpoint. Reporter: This morning, bartel is behind bars, as the community tries to come to grips with a brutal murder, that may have been rooted in a high school crush. Police say he had recently made internet searches, including serial killers by numbers of victims. Between now and then, doctors will evaluate his mental state. Let's bring in dan abrams for more on this. Dan, the details here, so grisly. Ankles and wrists tied, gagged. And how they were able to figure this out and use those pieces of evidence is fascinating. Interviewing him in connection with another assault, start to get suspicious. Ask him some questions. Doesn't quite admit it. But then, they go back. They find surveillance video. They find fingerprints. They find dna evidence. That's when they arrest him in connection with this case, all based on the rope and the duct tape and the ties. As you point out, this evidence just keeps piling up, and piling up, including the internet searches that linzie talked about. It sounds like his attorney is saying, the first thing we want to do is find out is he competent to stand trial? That's different from insanity. Insanity is did he know right from wrong? Competency to stand trial is a lower standard. Can you sit there and help your lawyer present your defense? Do you understand the proceedings against you. That's not a high bar to clear. Really low bar. But it certainly -- that's not the way you start the case if your position is he's absolutely not guilty. He had nothing to do with this. It's rare that's going to be your defense, that you start out by saying I want to determine if my client's competent to stand trial. Thank you, guys. Now, to the dramatic 911

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